CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums

Search Results

Register Blogs Community New Posts Updated Threads Search

Page 1 of 4 1 23 Last »
Showing results 1 to 25 of 97
Search took 0.01 seconds. Search: Posts Made By: mkhm
Forum: OpenFOAM Running, Solving & CFD September 7, 2023, 09:56
Replies: 0
Views: 199
Posted By mkhm
Pressure recovery: how to set BCs

Hi foamers,

As the title suggests, I would like to transition from a low pressure at the inlet to a higher pressure at the outlet. However, this doesn't appear to be straightforward, and the...
Forum: OpenFOAM Running, Solving & CFD September 7, 2023, 09:34
Replies: 1
Views: 359
Posted By mkhm
I think the problem for OpenFOAM is how to go...

I think the problem for OpenFOAM is how to go from a low pressure to high pressure. While I am expecting it to follow the isentropic relationship, the fact of having higher pressure at output than...
Forum: OpenFOAM Running, Solving & CFD September 6, 2023, 08:29
Replies: 1
Views: 359
Posted By mkhm
HELP: Subsonic Outlet Boundary Condition

I have a diffuser where the flow is supersonic in the converging part and subsonic in the divergent part. I am using my own 1D solver built based on rhoCentralFoam, which has been verified and tested...
Forum: OpenFOAM Running, Solving & CFD August 15, 2022, 04:17
Replies: 0
Views: 537
Posted By mkhm
OpenFOAM: sensible enthalpy/internal energy for a reactive case

Hi foamers,


I have a question regarding the calculation of the sensible enthalpy/interal energy.
I first start by explaining what I expect to see in the algorithem based on thermodynamic text...
Forum: Main CFD Forum February 8, 2021, 10:00
Replies: 8
Views: 734
Posted By mkhm
My case is not combustion related chemistry and...

My case is not combustion related chemistry and the chemical reactions must occur within the nozzle.
Forum: Main CFD Forum February 8, 2021, 09:58
Replies: 8
Views: 734
Posted By mkhm
Thanks for your reply. To sum up: First...

Thanks for your reply.
To sum up:
First step, it would be to design the nozzle depending on the gamma parameter. The only example in my mind (if you have another example, please mention it) it is...
Forum: Main CFD Forum February 8, 2021, 04:49
Replies: 8
Views: 734
Posted By mkhm
you are right when you say that even in...

you are right when you say that even in non-reactive case, gamma can change and the question persists independently from the fact that there are reactions or not. Agree. But, lets say that the impact...
Forum: Main CFD Forum February 8, 2021, 02:25
Replies: 8
Views: 734
Posted By mkhm
LuckyTran, thanks for your answer. My question is...

LuckyTran, thanks for your answer. My question is not related to simulation settings. It's more a fundamental question. I don't have a combustion case but that would not change the nature of problem....
Forum: Main CFD Forum February 7, 2021, 08:07
Replies: 8
Views: 734
Posted By mkhm
nozzle optimization to avoid heat release by reactive flow

Hi experts in fluid mechanics,

The case that I have to consider is a supersonic reactive flow.

The nozzle is designed such that the desired Mach number at the nozzle outlet is obtained in a...
Forum: OpenFOAM Programming & Development February 5, 2021, 09:21
Replies: 3
Views: 922
Posted By mkhm
warning: [-Wunused-variable]

Hi foamers,
I have a solver and I used it for quite a while. It retrieve data from a table and read it and use it (I am 100% sure as I did some validations against experimental data). However,...
Forum: OpenFOAM Programming & Development February 5, 2021, 07:48
Replies: 2
Views: 1,666
Posted By mkhm
Did you find any solution to your problem ? I do...

Did you find any solution to your problem ? I do have the same issue:
a warning about an unused variable. But I am 100% it is used.
Forum: ParaView September 24, 2020, 02:43
Replies: 0
Views: 817
Posted By mkhm
Parview: save screenshot in a specific size readable for Matlab

Hi,

I want to compare my results of Matlab with the results of OpenFoam shown in Paraview. The question is the following: how can I save the results of Paraview in an appropriate size (only the...
Forum: OpenFOAM Post-Processing September 8, 2020, 14:31
Replies: 4
Views: 890
Posted By mkhm
Thanks Mark for your reply. "surfaceCoarsen" is...

Thanks Mark for your reply. "surfaceCoarsen" is an utility, no ? How I can use it ? Could you please give an example ? Can it be used in the sampleDict ?
Forum: OpenFOAM Post-Processing September 8, 2020, 14:05
Replies: 4
Views: 890
Posted By mkhm
OpenFoam sampleDict surfaces: how to limit the number of points being sample ?d

Hi foamers,



I want to make a contour plot of a slice of my geometry for which the simulation is done in OpenFoam. So the best is to sample a surface. I succeed to do that but the amount of...
Forum: OpenFOAM Pre-Processing August 31, 2020, 06:19
Replies: 8
Views: 4,919
Posted By mkhm
Dear Tobias and Bruno, I have similar errors...

Dear Tobias and Bruno,

I have similar errors for concave cells. The checkMesh runs fine but checkMesh -allGeometry indicates that it fails (Failed 1 mesh checks). The cases were running fine and I...
Forum: OpenFOAM Meshing & Mesh Conversion August 30, 2020, 13:04
Replies: 4
Views: 8,340
Posted By mkhm
Is it possible that the simulations run fine and...

Is it possible that the simulations run fine and converge with concave cells ?

I have this issue. I did my simulations and I did not even realize that there was a problem related to concave...
Forum: OpenFOAM Programming & Development August 14, 2020, 09:18
Replies: 1
Views: 555
Posted By mkhm
In other terms, could we replace maxValU[/CODE]...

In other terms, could we replace maxValU[/CODE] simply by: max(mag(U_f)-mag(U_0)) ?


forAll(U_f,i)
{
DiffRhoU =mag(mag(U_f[i])-mag(U_0[i]));
if(DiffU>maxValU)...
Forum: OpenFOAM Programming & Development August 14, 2020, 06:46
Replies: 1
Views: 555
Posted By mkhm
Velocity in OpenFoam

Hi foamers,

My question is simple: U for each cell has 3 components for a 3D case and U is calculated for the whole domain, so many cell. Imagine that I want to find out the maximum value of the...
Forum: OpenFOAM Running, Solving & CFD August 3, 2020, 13:41
Replies: 7
Views: 1,326
Posted By mkhm
Thanks USV for your reply. I attach the plot of...

Thanks USV for your reply. I attach the plot of residuals. My supervisor had told me that the residuals should usually decrease for 3 order of magnitude. You can see in the attached file that is not...
Forum: OpenFOAM Running, Solving & CFD August 3, 2020, 03:48
Replies: 7
Views: 1,326
Posted By mkhm
Dear USV, I do consider what you call as the...

Dear USV,
I do consider what you call as the subsequent time steps as follows :

volScalarField rho_0("rho_0", rho);
solve(fvm::ddt(rho) + fvc::div(phi));
volScalarField rho_f("rho_f", rho);...
Forum: OpenFOAM Running, Solving & CFD July 31, 2020, 09:57
Replies: 7
Views: 1,326
Posted By mkhm
Dear dlahaye, 1. I think whether you do...

Dear dlahaye,
1. I think whether you do mag(something_1).value() / mag(something_2).value() or (mag(something_1/something_2)).value(), they are both equivalent. However, I don't understand why this...
Forum: OpenFOAM Running, Solving & CFD July 31, 2020, 04:50
Replies: 7
Views: 1,326
Posted By mkhm
Residuals of rhoCentralFoam

Dear foamers,



I am struggling to find a way to have a better insight of convergence of simulations done with rhoCentralFoam as the latter does not print residuals. I tried three ways but...
Forum: OpenFOAM Running, Solving & CFD June 3, 2020, 14:29
Replies: 0
Views: 698
Posted By mkhm
inviscid rhoCentralFoam: residuals -> convergence ?

Dear foamers,



I am using rhoCentralFoam with no viscosity. So the solver is explicit and there is no residuals being printed. However, I need to show somehow that my cases are converged. What...
Forum: Mesh Generation & Pre-Processing May 2, 2020, 04:20
Replies: 3
Views: 1,934
Posted By mkhm
No one can help me ?

No one can help me ?
Forum: OpenFOAM Running, Solving & CFD April 29, 2020, 14:14
Replies: 3
Views: 1,397
Posted By mkhm
Have a look at this webpage: ...

Have a look at this webpage:
http://www.tfd.chalmers.se/~hani/kurser/OS_CFD/


They have very good tutorials.
Showing results 1 to 25 of 97
Page 1 of 4 1 23 Last »

 
Forum Jump

All times are GMT -4. The time now is 00:25.

Contact Us - CFD Online - Privacy Statement - Top